Linear Equation Solver Calculator

Solve linear equations of the form ax + b = cx + d and find the value of x that satisfies the equation. Visualize the solution with an interactive graph.

The coefficient of x on the left side of the equation
The constant term on the left side of the equation
The coefficient of x on the right side of the equation
The constant term on the right side of the equation

How to Use This Calculator

  1. Enter the coefficient of x on the left side of the equation (a)
  2. Enter the constant term on the left side of the equation (b)
  3. Enter the coefficient of x on the right side of the equation (c)
  4. Enter the constant term on the right side of the equation (d)
  5. Click Calculate to find the value of x that satisfies the equation

Formula Used

x = (d - b) / (a - c)

Where:

  • a = Coefficient of x on the left side of the equation
  • b = Constant term on the left side of the equation
  • c = Coefficient of x on the right side of the equation
  • d = Constant term on the right side of the equation

Example Calculation

Real-World Scenario:

Imagine you're comparing two pricing plans. Plan A costs $5 per month plus $2 per hour of usage. Plan B costs $10 per month plus $1 per hour of usage. You want to find out how many hours of usage would make both plans cost the same.

Given:

  • Plan A: $5 + $2x (where x is hours of usage)
  • Plan B: $10 + $1x

Equation:

5 + 2x = 10 + 1x

Calculation:

2x - 1x = 10 - 5
x = 5

Result: At 5 hours of usage, both plans cost the same ($15).

Why This Calculation Matters

Practical Applications

  • Finding break-even points in business
  • Solving word problems in mathematics
  • Determining equilibrium in economic models
  • Analyzing linear relationships in science

Key Benefits

  • Quickly solves linear equations without manual calculations
  • Helps visualize the solution point of two linear expressions
  • Reduces errors in algebraic manipulations
  • Saves time on homework and professional calculations

Common Mistakes & Tips

When a = c, the equation has no unique solution (either no solution or infinitely many solutions). In this case, the calculator will indicate that the equation has no unique solution because it would require division by zero.

When entering negative coefficients or constants, make sure to include the negative sign. For example, if the equation is 2x - 5 = -x + 3, you should enter -5 for b and -1 for c.

Frequently Asked Questions

If a = c, then the equation either has no solution or infinitely many solutions. If b = d, then the equation has infinitely many solutions (any value of x will satisfy the equation). If b ≠ d, then the equation has no solution.

Yes, this calculator can handle equations with fractions or decimals. Simply enter the coefficients and constants as decimal numbers. For example, for the equation 0.5x + 1.5 = 2x - 0.5, you would enter 0.5 for a, 1.5 for b, 2 for c, and -0.5 for d.

For an equation like 3x + 5 = 0, you can rewrite it as 3x + 5 = 0x + 0. So you would enter 3 for a, 5 for b, 0 for c, and 0 for d. The calculator will then solve for x.

References & Disclaimer

Mathematical Disclaimer

This calculator provides solutions to linear equations of the form ax + b = cx + d. While we strive for accuracy, users should verify results independently, especially for critical applications. The calculator is designed for educational and reference purposes.

References

Accuracy Notice

This calculator provides accurate results for linear equations with real coefficients. For complex equations or equations with special cases (such as division by zero), additional analysis may be required. Results are rounded to 6 decimal places for display purposes.

About the Author

Kumaravel Madhavan

Web developer and data researcher creating accurate, easy-to-use calculators across health, finance, education, and construction and more. Works with subject-matter experts to ensure formulas meet trusted standards like WHO, NIH, and ISO.

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